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What numbers multiply to -30 and add to -3

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Let the numbers be x and y. Then xy = -30 and x+y = -3.

Solve xy = -30 for y: y = -30/x

subst. -30/x for y in x+y= -3: x - 30/x = -3

Multiply all 3 terms by x: x^2 - 30 = -3x, so x^2 + 3x - 10 = 0

Solve this quadratic equation for x. x: {-5, 2}

If x = -5, then x+y = -3 becomes -5 + y = -3, and y = 2.

You should check to determine whether x=2 is also correct. If it is, what is the corresponding y value?
User Inazense
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